renwick



4 Sheets-Sheet 1.

E. s. RENWICK. THERMOSTAT FOR INGUBATORS.

(No Model.)

Patented July 17, 1883.-

"WITNESSES INVENTOR N. PETERS, Phnlo-Lilhngnpher. Washingwn. n. c.

(No Model.) 4 SheetsSheet 2. E. S. RENWIGK. THERMOSIAT FOR INGUBATORS.

No. 281,397. Patented July 17,1883.

I INVENTOR WITNESSES: I I

N4 PETERS. Phewmhn n mr. Wahmginn. n. c.

(No Model.) 4 Sheets ee E. s. RENW K. THERMOSTAT FOR BATOR S.

TNVENTOR (No Model.) v sheets-sheet 4.

E. S. RENW'IGK. THERMOSTAT-FO'R INOUBATORS.

No. 281,397. I 1 Patented July 1'7, 1883.

WITNESSES; V I INVENITYOR %Mmw N. PUERs Phuwmho lm, Waahington. D. c.

end view of the same.

UNITED STATES PATENT OFFICE.

EDWARD S. RENWIOK, OFEMILLBURN, N EWV JERSEY.

TH ERMOSTAT .|NCUBATORS.

SPECIFICATION forming part of Lettersi Patent No. 281,397, dated July 1'7, 1883.

Application filed September 4, 1882. (No model.)

To all whom it may concern.-

Be it known that I, EDWARD SABINE REN- WICK, of Millburn, in the county of Essex and State of New Jersey, have made an invention of certain new and useful Improvements in Incubators; and I do hereby declare that the following, taken in connection with the ac companyin'g drawings, is a full, clear, and exact description and specification of the same.

The object of. the present improvement is to simplify the construction of incubators and improve their operation; and to these ends the invention consists of certain new and useful combinations of devices which are recited in the claims at the close of this specification. The said combinations are described and were claimed in a specification made by me and dated the 11th day of January, A. D. 1882; but as the Commissioner of Patents has decided that these combinations could not be embraced in the same patent with other combinations which formed parts of my complete incubator, the former are claimed under this division of my invention, while the claims to the latter are retained in another division of my invention. In order that these combinations may be understood, I have represented in the accompanying drawings, and will proceed to describe, the best mode in which I have embodied the same for practical use, it being understood that the mode of embodying the improvements may be modified as circumstances or the views of different constructers may render expedient.

Figure 1 of said drawings represents a front View of the incubator. Fig. 2 represents an Fig. 3 represents a plan of the same. Fig. 4 represents a transverse section of the incubator at the line :0 w of Fig. 3. Fig. 5 represents a central longitudinal section .of the same. Fig. Grepresents a horizontal section of the incubator at represent views of various portions of the in cubatorFigs. 10 to 13 and 15 to 17 of half the working dimensions, and Fig. 14 being of full size.

The incubator represented in the said draw- V ings embodies improvements recited in previous patents granted to me, as well as those recited in the claims at the close of this specification, A A being the incubating-chamber; BB, the egg-holders in theform of drawers, (fitted either with rollers or with perforated botto1ns;) d, the heat-fines; I, the waste-heat chimneys; E E, the chimney-va1ves5 G, the ventilating-chimney; K, the ventilating-valve; J J, the air-supply pipes; M M, the water-trays, open at their tops; N N, the water-founts'; QQ, the water-basins, connected with the watertrays by tubes; and e e, the horizontal portions of the flues. As all the said parts of the illcubator represented in the drawings are fully described in the said previous specification, dated January 11, A. D. 1882, it is not deemed necessary to describe them minutely herein.

The egg-holders B B are arranged in pairs, back to-back, with their backs separated by a space which is wide enough to receive the thermostat S, which is placed between the eggholders,- so that it is at the level of the eggholders, or thereabout, and is affected by substantially the same changes of heat that affects the eggs in the egg-holders, thus causing the thermostat to be a more reliable indicator of such changes than it is when placed in the top of the incubating-chamber or in a separate compartment connected with that chamber.

According to the present invention the thermostat is constructed to operate by its .tensile force. It is composed of a tensile strip of vulcanite (hard rubber) sustained by a frame. The expansive tensile strip of vulcanite s in the incubator represented in the drawings is about thirty-nine inches long. Its frame (see more particularly Figs. 13, 14, 16, and 17) ismade by preference of two bars, tt, of dry wood, connected together by metallic mountings u a. Each end of the frame carries a lever. The lever V, at one end of the frame, is forked at its upper end to receive one end of the vulcanite strip 8, and is pivoted at. its lower end to the metal mounting a. At an intermediate part of this lever there is a swiveling nut, 10, to which the adjusting-screw W is fitted, so that the leverV becomes an adjustinglever, by which the expansive tensile strip may be adjusted longitudinally for use. The stem a hole in the adjacent end wall, a, (of Fig. 5,) of the incubator, so that the head of the adjusting-screw is at the exterior, where it may be conveniently turned without the necessity of opening the incubator. The lever V, at the opposite end of the incubator and frame, is used to transmit the motion by expansion and contraction of the expansile strip to the device to be controlled by it. This motiontransmitting lever V is of elbow form, is pivoted to the adjacent metal mounting, and is connected at its vibrating end with a second lever, V", by means of a link, '0. The end of the second lever, V is connected by a rod, Z, with the detent-lever \V of the valve-engine above, (see Fig. 15,) and the rock-shaft no of this detent-leveris fitted with a weighted arm, U, (which, if deemed best, may be replaced by a spring.) The strip of vulcanite is connected with the levers V V of the thermostat by pivots, and the levers, links, and rods are also connected by pivots. The levers are arranged, as represented in the drawings, (or in some other equivalent mode,) so that the expansile strip of vuleanite is subjected to the tensive strain of the weight U, whose force is multiplied by the action of the levers. Consequently the expansile strip of vulcanite s is constantly under a strong tensile strain far greater than the force it is required to exert to move the detent 1. Moreover, as the weight U is at one end of the system of connections with the detent 1, Figs. 13 and 15, of the valve-engine, while the expansile strip a is at the other end of the same system, and the two operate antagonistically, all the play of the connections is taken up, and the thermostat operates with great certainty and force. The holding of the expansile strip under a tensile strain between two levers, V V, enables one of them to be used with advantage to adjust the position of the strip longitudinally, as required, so that it may be set to operate the detent when the temperature is at the desired degree, while the other lever (at the opposite end of the said strip) transmits movement to the detent, multiplied in extent. This mode of holding the strip also incidentally permits the strip to be arranged above the frame upon which it is strained, so that it is exposed at both sides to the action of the heat of the atmosphere.

The dynamic or valve engine has preferably but one revolving shaft, N, which is fitted with a chain-wheel, O, and two detent-arms, S S. These arms operate in connection with the detent I, each arm having a cross end, 8, fitted to pass through the slot of the detent when the slot is moved to the proper position by the action of the thermostat S. One of the arms is longer than the other, so that their ends are at different radial distances from the axis of the main shaft N. Consequently, when the detent is moved to a position to permit one arm, S", to escape through the detent-slot 2', Fig. 15, the face of the detent is in position to stop the other arm, S, when the engine-shaft N has made half of a revolution. The chainwheel 0 receives the chain of the-weight 0, Figs. 1 and 2, by which the requisite power to move the valves is supplied; and it is expedient to apply a ratchet-wheel, R, to the engine-shaft N, with a pawl upon the engineframe, to prevent the accidental backward movement of the engine-shaft. The engineshaft N is fitted with a crank, whose crankpin is connected by a rod, 1, Fig. 5, with the arm 0 of the valve rock-shaft D. whose ends are fitted to rock in hearings in the heads of the standards I) b. The rock-shaft D carries the arms I) If, Figs. 2 and 3, from the ends of which the valves E, which control the wasteheat chimneys I I, are suspended, the valves being raised to open these chimneys and permit the heat from the lamps to escape when the heat of the incubating-chamber rises, and being dropped to close the waste-heat chimneys when the heat in the incubating-chamber falls below the mean temperature. The same valve rock-shaft is connected by an arm, I)", a rod, m, (passing through a hole in the wall of the ventilating-chimney,) an elbow lever, I), with the ventilating-valve K, so that the valve is raised or opened and is dropped or closed simultaneously with the opening and closing of the chimney-valves E E.

A liquid speed-controller is employed to prevent the engine'shaft N from moving with too great speed. In a previous patent l. have described sueh a controller as made separately from the engine, but combined with it. I11 the present case the paddle-arms y of the paddles y of the speed-controller are connected directly with the engine-shaft at about the center of the engine-frame, and the trough F (shown in dotted lines in Fig. 15) of the controller is sccured to the cross-bars a a of the said frame,

so that the members of the liquid speed-controller are held in the proper relationship by the engine-frame.

The weight-chain M and weights 0 O are arranged, by preference, according to the Huyghens system, the chain M being continuous and being applied to the pulleys d d (see Fig. 1) of two weights, 0 O, of which one, 0", is lighter than the other, 0, by being made hollow, and the shaft of the counter chainwheel 0, Figs. 1 and 2, being fitted with a ratchet-wheel controlled by a pawl, (or a pawl being fitted to operate directly upon the chainwheel,) so that the power-weight 0 may be wound up by turning counter chain-wheel 0 without affecting the engine. It is also expedient to connect the two weights by a chain, M of double the lineal weight of the main chain M, so that the strain upon the engine is not varied by changes in the position of the weights. It is also expedient to cover the act upon one end thereof, and the adjusting l lever and screw at the opposite end thereof.

2. The combination, substantiallyas before set forth, of the expansile strip of the thermostat and the frame thereof with a weight by which the said strip is subjected to a strong tensile strain. I a

3. The combination, substantially as before set forth, of the thermostat, the detent moved thereby, the revolving shaft carrying the de tent-arms, the paddle-arms, also carried by said shaft, the trough through which said paddlearms move, and the engine-frame holding the said detent-shaft, detent-arms, paddle-arms,

and trough in their proper relative positions.

4. The combination, substantially as before set forth, of the walls of the incubator, the eX- pansile strip of the thermostat inclosed therein, the weight operating upon one end of said strip to subject it to a tensile strain, and the 20 EDWARD SABINE RENWIGK.

' l/Vitnesses:

a B. E. J .EILS,

EWD. F. WALKER. 

